Automatic disambiguation based on a reference resource

ABSTRACT

A novel system for automatically indicating the specific identity of ambiguous named entities is provided. An automatic disambiguation data collection is created using a reference resource. Explicit named entities are catalogued from the reference resource, together with various abbreviated, alternative, and casual ways of referring to the named entities. Entity indicators, such as labels and context indicators associated with the named entities in the reference resource, are also catalogued. The automatic disambiguation collection can then be used as a basis for evaluating ambiguous references to named entities in text content provided in different applications. The content surrounding the ambiguous reference may be compared with the entity indicators to find a good match, indicating that the named entity associated with the matching entity indicators is the intended identity of the ambiguous reference, which can be automatically provided to a user.

BACKGROUND

The ability to identify named entities, such as people and locations,within a document, has been established as an important task in areassuch as topic detection and tracking, machine translation, andinformation retrieval. A user may perform a search of the Web or anotherresource for a particular person, place, or other specific entity, byentering a string of text characters that constitutes an orthographicrepresentation of a common name for the entity, as a query in a searchengine. However, this string of text may also refer to other, unrelatedentities or meanings that are irrelevant to the intended search results,while many relevant references may use other variations on theorthographic representation of the entity, and thereby be missed by thesearch engine given the particular string of text. For example, a searchbased on the string of text “George W. Bush” might return results thatinstead reference the earlier American president, George H. W. Bush, orGeorge Bush International Airport in Houston, the aircraft carrierGeorge H. W. Bush, other famous people, places, or entities with “Bush”in their name, or to a literal “bush” or shrub as a category of plant. Asearch may also miss alternate “surface forms”, or alternateorthographic references to the same intended entity, such as a referencewith an abbreviated, alternate, casual, or other context-specific formof the name of the intended entity. For instance, alternate surfaceforms for George W. Bush that are used in various documents available onthe Web may include “President Bush”, “Bush 43”, or even anorthographically unrelated term such as “Dubya”. Other Web-availablereferences might reference Ronald Reagan as “The Gipper” or AbrahamLincoln as “Honest Abe”. Any of these documents might contain valuableinformation that would be desirable to include in search results for asearch for the respective entities, but may be missed using a search fora string of text that represents the standard surface form forrepresenting the respective entities. It would therefore be highlydesirable to identify text references to particular named entitiesconsistently with all the various surface forms in which such referencesmay occur.

While the intended entity for an ambiguous surface form might be quiteclear to many informed readers due to context in some instances, forexample “Bush delivered his State of the Union address to Congress”,many other instances may be more ambiguous, e.g., “Bush delivered thecommencement address at the university”. In the latter example, thesurface form “Bush” may actually refer to former president George H. W.Bush or to former Florida governor Jeb Bush, for example, and readersunfamiliar with the event covered would not be able to resolve itcorrectly. In addition, with text content distributed around the worldon the Internet, it is to be expected that many readers of any contentmight be from backgrounds that do not dispose them to understand theentire context that a writer would take for granted. An effective way toprovide explicit disambiguation of ambiguous surface forms for specificentities would therefore fulfill a broad and persistent need.

The discussion above is merely provided for general backgroundinformation and is not intended to be used as an aid in determining thescope of the claimed subject matter.

SUMMARY

A novel system for automatically indicating the specific identity ofambiguous named entity mentions is provided. An automatic disambiguationdata collection may be created using a reference resource. Explicitnamed entities may be catalogued from the reference resource, togetherwith various abbreviated, alternative, and casual ways of referring tothe named entities. Entity indicators, such as labels and/or contextindicators associated with the named entities in the reference resource,may also be catalogued. The automatic disambiguation collection may thenbe used as a basis for evaluating ambiguous references to named entitiesin text content provided in different applications. The contentsurrounding the ambiguous reference may be compared with the entityindicators to find a good match, indicating that the named entityassociated with the matching entity indicators is the intended identityof the ambiguous reference, which may be automatically provided to auser. A computing device may therefore provide unambiguous indicationsof the particular named entity referred to by potentially ambiguoussurface forms in various documents.

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used as an aid in determining the scope of the claimed subjectmatter. The claimed subject matter is not limited to implementationsthat solve any or all disadvantages noted in the background.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a block diagram for a software system for automaticdisambiguation, according to an illustrative embodiment.

FIG. 2 depicts a screenshot of an application displaying text content,with disambiguation outputs provided by an automatic disambiguationapplication, according to an illustrative embodiment.

FIG. 3 depicts a flow diagram for a method for preparing and applying anautomatic disambiguation system, according to an illustrativeembodiment.

FIG. 4 depicts a block diagram of a computing environment in which someembodiments may be practiced, according to an illustrative embodiment.

FIG. 5 depicts a block diagram of a mobile computing environment inwhich some embodiments may be practiced, according to an illustrativeembodiment.

DETAILED DESCRIPTION

FIG. 1 depicts a block diagram for a software system 100 for automaticdisambiguation, according to an illustrative embodiment. For example,software system 100 may include one or more databases and other softwarestored on a computer-readable medium. These may include, for example, asurface form reference database 101 with a collection of referencesurface form records 103, 105; and a named entity reference database 121with a collection of reference named entity records 123, 125, in thisillustrative embodiment. The surface form reference database 101contains different surface forms, which are defined as alternative wordsor multi-word terms that may be used to represent particular entities.Each of the reference surface form records 103, 105 is indexed with oneor more named entities 111 associated with one or more of the referencenamed entity records 123, 125. Each of the reference named entityrecords 123, 125 is in turn associated with one or more entityindicators, which may include labels 131 and/or context indicators 133in this embodiment. The labels 131 and context indicators 133 may beextracted from one or more reference works or other types of informationresources, in which the labels 131 and context indicators 133 areassociated with the named entity records 123, 125. Various embodimentsmay make use only of labels as entity indicators, or only of contextindicators as entity indicators, or both. Various embodiments are alsonot limited to labels and context indicators as entity indicators, andmay also use additional types of entity indicators, in any combination.

Software system 100 is enabled to disambiguate a polysemic surface formand associate an entity to it, from among different named entities, suchas persons, places, institutions, specific objects or events, or areotherwise referred to with proper names. Named entities are oftenreferred to with a variety of surface forms, which may for example bemade up of abbreviated, alternative, and casual ways of referring to thenamed entities. One surface form may also refer to very differententities. For example, different instances of the surface form “Java”may be annotated with different entity disambiguations, to refer to“Java (island)”, “Java (programming language)”, “Java (coffee)”, etc.,in one exemplary embodiment. A user interested in gaining informationabout the island of Java will therefore be able to reliably and easilyhome in on only those references that actually refer to the island ofJava, in this example. Any document may be interpreted as a collectionof references to particular named entities, so that the named entitiescan be dealt with directly for navigating and using the informationcontained in the documents. For example, a user selection of a surfaceform may lead to a Web search, a news search, or a search of an indexedcollection of documents, for the entity indicated by the surface form,in different embodiments.

For example, in the illustrative embodiment of FIG. 1, reference surfaceform record 103 is for the surface form “Columbia”, as indicated at therecord's title 107. The surface form “Columbia” is associated inreference surface form record 103 with a variety of named entities thatmight be referred to by the surface form “Columbia”, an illustrativesample of which are depicted in FIG. 1. These include “Colombia(nation)”, which has a minor difference in spelling but often anidentical pronunciation to surface form 107; Columbia University; theColumbia River; a hypothetical company called the Columbia RocketCompany; the Space Shuttle Columbia; the USS Columbia; and a variety ofother named entities. The variation in spelling between “Columbia” and“Colombia” is another example of different surface forms that mayrepresent the same named entity; for example, a Web search for “BogotaColumbia” returns a large fraction, about one third, as many searchresults as a Web search for “Bogota Colombia”.

Reference named entity record 123 illustrates one example of a referencenamed entity in named entity reference database 121 that may be pointedto by one of the named entities 111 associated with reference surfaceform record 103. Reference named entity record 123 is for the namedentity 127, “Space Shuttle Columbia”, and is associated with a varietyof entity indicators. The entity indicators include labels 131 andcontext indicators 133, in this illustrative embodiment. The labels 131illustratively include “crewed spacecraft”, “space program fatalities”,“space shuttles”, and “space shuttle missions”, while the contextindicators 133 illustratively include “NASA”, “Kennedy Space Center”,“orbital fleet”, “Columbia Accident Investigation Board”, “Spacelab”,and “Hubble Service Mission”, in the embodiment of FIG. 1. The labels131 and context indicators 133 are used as bases for comparison with atext in which an ambiguous surface form appears, to evaluate what namedentity is intended by the surface form, and are explained in additionaldetail below. The particular labels 131 and context indicators 133depicted in FIG. 1 are provided only as illustrative examples, while anyother appropriate entity indicators might be associated with thereference named entity “Space Shuttle Columbia”, and any of a variety ofother named entities may be associated with the surface form “Columbia”.Additionally, other reference surface forms may also be used, with theirassociated named entities, and with the appropriate entity indicatorsassociated with those reference named entities.

FIG. 2 depicts a screenshot 200 of a text-associated application thathas provided a text panel 201, according to one illustrative embodiment.Text panel 201 provides an example of a text in which several surfaceforms may appear, and for which the software system 100 of FIG. 1 mayprovide automatic disambiguation and mapping to the reference entities.The application that provides text panel 201 may, for example, be a webbrowser with a website loaded, a reference work application, or an emailapplication, for example.

In one illustrative embodiment, a user may use a pointer 203 to indicateor select a surface form, such as by manipulating a mouse or trackballto move pointer 203 in position over a surface form, such as by clickingon the surface form, or merely by hovering the pointer 203 over thesurface form, in different embodiments. FIG. 2 illustrates the pointer203 being used in several different positions in a text, to selectsurface forms 211, 213, 215, 217, and 219, for which a disambiguationsystem respectively provides disambiguation outputs 221, 223, 225, 227,and 229. As particular illustrative examples, surface form 211 for“Astro” is disambiguated to mean the named entity 221, the “Astro-2Ultraviolet Mission”; surface form 213 for “Columbia” is disambiguatedto mean the named entity 223, the “Space Shuttle Columbia”; surface form215 for “Columbia” is disambiguated to mean the named entity 225,“Columbia University” (the differing disambiguations of the same surfaceform is elaborated on further below); surface form 217 for “CapeCanaveral” is disambiguated to mean the named entity 227, “LaunchComplex 39” near Cape Canaveral; and surface form 219 for “Florida” isdisambiguated to mean the named entity 229, for “Florida (U.S. state)”,as opposed, for example, to a reference to the University of Florida.These illustrative disambiguation outputs are provided by adisambiguation system, illustratively such as software system 100 ofFIG. 1, and displayed near the pointer 203 for each of the selectedsurface forms.

For example, when surface form 213, “Columbia”, is selected, thedisambiguation system provides a disambiguation output 223, which reads“Space Shuttle Columbia”, referring to the specific surface form andnamed entity illustratively depicted in the reference surface formrecord 103 and the reference named entity record 123 in FIG. 1. This andthe other particular surface forms and named entities depicted in FIG. 2are illustrative only, and any other reference to a named entity in anykind of text, including a language input in another form of media thatis converted into text, may be acted on by a disambiguation system toprovide disambiguation outputs for polysemic surface forms and explicitannotations identifying the entities intended to be referenced byvarious surface forms.

How the disambiguation system works, to provide the disambiguationoutputs 221, 223, 225, 227, and 229 respectively for the selectedsurface forms 211, 213, 215, 217, and 219, according to one illustrativeembodiment, is depicted in reference to an illustrative method 300 inFIG. 3.

FIG. 3 depicts method 300 for providing a disambiguation output for anambiguous surface form, in one illustrative example. Method 300 includestwo high-level portions, in this embodiment: procedure 301, forpreparing an automatic disambiguation system, and procedure 321, forapplying the automatic disambiguation system. Procedure 301 mayillustratively include assembling the reference surface forms,associated reference named entities, and associated entity indicators ofsoftware system 100 in FIG. 1, for example, while procedure 321 mayillustratively include using software system 100 in the process ofproviding disambiguation outputs in response to a user selectingambiguous reference forms in text panel 201 of FIG. 2, for example.

According to the illustrative embodiment of FIG. 3, procedure 301illustratively includes step 311, of extracting a set of surface formsand entity indicators associated with a plurality of named entities fromone or more information resources. Procedure 301 may further includestep 313, of storing the surface forms and named entities in a surfaceform reference, comprising a data collection of surface form recordsindexed by the surface forms and indicating the named entitiesassociated with each of the surface forms. Procedure 301 may alsoinclude step 315, of storing the named entities and entity indicators ina named entity reference, comprising a data collection of named entityrecords indexed by the named entities and containing the entityindicators associated with each of the named entities.

Procedure 321 includes step 331, of identifying a surface form of anamed entity in a text, wherein the surface form is associated in asurface form reference with one or more reference named entities, andeach of the reference named entities is associated in a named entityreference with one or more entity indicators.

Procedure 321 further includes step 333, of evaluating one or moremeasures of correlation among one or more of the entity indicators, andthe text; step 335, of identifying one of the reference named entitiesfor which the associated entity indicators have a relatively highcorrelation to the text, where a correlation may be relatively high ifit is higher than a correlation with at least one alternative, forexample; and step 337, of providing a disambiguation output thatindicates the identified reference named entity to be associated withthe surface form of the named entity in the text. Step 333 may includeusing labels alone, context indicators alone, both labels and contextindicators, other entity indicators, or any combination of the above, asthe entity indicators used for evaluating correlation. Thedisambiguation process therefore uses the data associated with the knownsurface forms identified in the information resource, and any of a widevariety of possible entity disambiguations in the information resource,to promote the capacity for automatic indications of high correlationbetween information from a text that mentions a surface form of a namedentity, and the labels and context indicators stored in a named entityreference for that named entity, so that the reference to it in thedocument can be easily, automatically, reliably disambiguated.

Different embodiments may use different particular steps for any part ofprocedure 301, and are not limited to the particular examples providedin connection with FIG. 3. The illustrative steps depicted in FIG. 3 areelaborated on below.

Referring again to step 311, the information resources used forextracting the reference surface forms and entity indicators associatedwith named entities, may include a variety of reference sources, such asan electronic encyclopedia, a web publication, a website or relatedgroup of websites, a directory, an atlas, or a citation index, forexample. Different embodiments may use any combination of theseinformation resources, and are not limited to these examples, but mayalso include any other type of information resource.

For example, in one illustrative embodiment, an electronic encyclopediamay be used as an information resource from which to extract theinformation referred to in method 300. The electronic encyclopedia maybe distributed and accessed on a local storage device, such as a DVD, aset of CDs, a hard drive, a flash memory chip, or any other type ofmemory device, or it may be distributed and accessed over a networkconnection, such as over the Internet, or a wide area network, forexample. In another embodiment, the information resource may include awebsite, such as that of a large news organization, library, university,government department, academic society, or research database. Inanother embodiment, the information resource may include a largeresearch citation website or a website for uploading drafts of researchpapers, for example. In other embodiments, the information resource mayinclude a selected set of websites, such as a group of science-orientedgovernment websites that includes the content of the websites for NASA,the NOAA, the Department of Energy, the Centers for Disease Control andPrevention, and the National Institutes of Health, for example. Otherembodiments are not limited to these illustrative examples, but mayinclude any other type of information resource from which theappropriate information may be extracted.

In one illustrative embodiment, an electronic encyclopedia may includevarious encyclopedia entries, articles, or other documents about avariety of different named entities that include “Colombia”, “ColumbiaUniversity”, “Columbia River”, “Space Shuttle Columbia”, and so forth.The names for these named entities may serve as the titles for thearticles in the encyclopedia. As procedure 301 of preparing theautomatic disambiguation system is being performed, the information isextracted from the article entitled “Colombia (nation)”, including anindication that it is sometimes referred to under the spelling“Columbia”. A reference named entity record entitled “Colombia” iscreated in the named entity reference database 121, and the referencenamed entity “Colombia (nation)”, associated with the reference namedentity, is added to a reference surface form record for the surface form“Columbia” in a surface form reference database 101. Similarly,information is extracted from a document about “Columbia University” inthe electronic encyclopedia to create a reference named entity recordfor “Columbia University”, with the reference named entity added to therecord for reference surface form “Columbia”, information is extractedfrom an entry in the electronic encyclopedia entitled “Space ShuttleColumbia” to add the corresponding reference named entity record in thenamed entity reference database and an associated addition to the recordfor reference surface form “Columbia”, and so forth. The different steps311 and 313 may be repeated iteratively for each document or otherinformation resource from which information such as surface forms andentity indicators are extracted, or information from several documentsmay be extracted and then stored together, for example; the differentaspects of procedure 301 may be performed in any order.

Each of the named entities extracted from an information resource may bestored with associations to several surface forms. For example, thetitle of an article or other document may be extracted as a surface formfor the named entity to which it is directed. A named entity may oftenbe referred to by a surface form that unambiguously identifies it, andmay have a document in the information resource that is entitled withthat unambiguous name. The title of an encyclopedia article may alsohave a distinguishing characteristic added to the title, to keep thenature of the document free from ambiguity. For example, an article inan electronic encyclopedia on the U.S. state of Georgia may be entitled“Georgia (U.S. state)”, while another article may be entitled “Georgia(country)”. Both of these may be extracted as named entities, with bothof them associated with the surface form “Georgia”.

Information for the entity indicators may be collected at the same timeas for surface forms. In this case, for example, the other informationin these document titles could be stored among the labels 131 for therespective reference named entity records, so that the reference namedentity record on “Georgia (U.S. state)” includes the label “U.S. state”and the reference named entity record on “Georgia (country)” includesthe label “country”. The labels may constitute classifying identifiersapplied to the respective named entities in the encyclopedia or otherinformation source.

An electronic encyclopedia may also include documents such as a redirectentry or a disambiguation entry. For example, it may have a redirectentry for “NYC” so that if a user enters the term “New York City” in alookup field, the “NYC” redirect page automatically redirects the userto an article on New York City. This information could therefore beextracted to provide a reference named entity record for New York Citywith an associated surface form of “NYC”. Similarly, the surface form“Washington” and an associated context indicator of “D.C.” can beextracted from a document entitled “Washington, D.C.” Context indicatorsare discussed further below.

Another feature an electronic encyclopedia may use is a disambiguationpage. For example, the encyclopedia may have a disambiguation page forthe term “Washington” that appears if someone enters just the term“Washington” in a lookup field. The disambiguation page may provide alist of different options that the ambiguous term may refer to, withlinks to the specific documents about each of the specific namedentities, which may include “Washington, D.C.”, “Washington (U.S.state)”, “George Washington”, and so forth. Information could thereforebe extracted from this disambiguation page of the information resourcefor reference named entity records for each of the specific namedentities listed, with a surface form of “Washington” recorded for eachof them, and with context indicators extracted for each of the namedentities based on the elaboration to the term “Washington” used todistinguish the different documents linked to on the disambiguationpage.

Various other sources may also be used for extracting label and contextinformation for the reference named entity records. For example,different entries in the electronic encyclopedia may include categoryindicator tags, and the encyclopedia may include a separate page for acategory, showing all the entries that are included in that category.For example, the entries for “Florida” and “Georgia (U.S. state)” mayboth include category tags labeled “Category: U.S. States”. Theencyclopedia may also include separate pages for lists, such as a pageentitled, “List of the states in the United States of America”, witheach entry on the list linked to the individual encyclopedia entry forthat state.

Labels are not limited to the particular examples discussed above, suchas title information, categories and other types of tags, and listheadings, but may also include section names or sub-headings withinanother article, or a variety of other analogous labeling information.

Context indicators are other types of entity indicators that may beextracted from an electronic encyclopedia or other information resourceand applied to respective named entities, either alone or together withlabels, among other combinations, in different embodiments. Contextindicators may include attributes such as elements of text associatedwith their respective named entities, by means of an association such asproximity in the title of an article in an encyclopedia or other type ofinformation resource, proximity to the name of the named entity in thetext of an entry or article, or inclusion in a link to or from anotherentry directed to another named entity in the information resource, forexample. As examples of linking context indicators, an article about theSpace Shuttle Columbia may include a reference to its serving mission tothe Hubble Space Telescope, with the phrase “Hubble Space Telescope”linked to an article on the same; while another article on the KennedySpace Center may include a reference to the “Space Shuttle Columbia”with a link to that article. The titles of articles linking both to andfrom the article on the space shuttle Columbia may be extracted ascontext indicators in the named entity reference record for “SpaceShuttle Columbia”. Other types of context indicators may also be used,that are not limited to these illustrative examples.

Context indicators and labels may both provide valuable indicators ofwhat particular named entity is intended with a given surface form. Forexample, the electronic encyclopedia may include an article thatcontains both the surface forms “Discovery” and “Columbia”. Theirinclusion in the same article, or their proximity to each other withinthe article, may be taken as a context indicator of related content, sothat each term is recorded as a context indicator associated with thenamed entity reference of the other term, under the specific namedentity reference records for “Space Shuttle Discovery” and “SpaceShuttle Columbia” in the named entity reference database. Additionally,both terms may appear in an article entitled “Space shuttles”, and theyboth may link to several other articles that have a high rate of linkingwith each other, and with links to and from the article entitled “Spaceshuttles”. These different aspects may be translated into contextindicators recorded in the named entity references, such as a contextindicator for the term “space shuttle” in both of the named entityreference records. It may also be used to weight the context indicators,such as by giving greater weight to context indicators with a relativelyhigher number of other articles that also have links in common with boththe named entity and the entity indicator.

Weighting the relevance of different entity indicators may also take theform of weighting some entity indicators at zero. This may be the caseif a very large amount of potential entity indicators are available, andcertain criteria are used to screen out identity indicators that arepredicted to be less relevant. For example, context indicators may beextracted and recorded to a named entity reference record only if theyare involved in an article linked from the article for the named entitythat also links back to the article for the named entity, or if thearticle for a candidate context indicator shares a threshold number ofadditional articles to which it and the article for the named entityshare mutual links. Techniques such as these can effectively filtercandidate context indicators to keep unhelpful indicators out of thenamed entity reference record.

Additionally, both the “Space Shuttle Discovery” and “Space ShuttleColumbia” articles in the electronic encyclopedia may include categorytags for “Category: Crewed Spacecraft” and “Category: Space Shuttles”.They may both also include a list tag for “List of AstronauticalTopics”. These category and list tags and other potential tags may beextracted as labels for the named entity references for both namedentities. The quantity of different labels and context indicators incommon between the two named entity references could contribute to ameasure of correlation or similarity between the two named entityreferences.

Returning to procedure 321, with the automatic disambiguation systemprepared by procedure 301, it is ready to use to disambiguate namedentities in a subject text. This subject text may be from a web browser,a fixed-layout document application, an email application, a wordprocessing application, or any other application that deals with thepresentation of text output.

Procedure 321 may also include some pre-processing steps to facilitateidentifying the surface forms of named entities. For example, the systemmay split a document into sentences and truecase the beginning of eachsentence, hypothesizing whether the first word is part of an entity orit is capitalized because of orthographic conventions. It may alsoidentify titles and hypothesize the correct case for words in thetitles.

In a second stage of pre-processing the text, a statistical named-entityrecognizer may identify boundaries of mentions of the named entities inthe text, and assign each set of mentions sharing the same surface forma probability distribution over named entity labels, such as Person,Location, Organization, and Miscellaneous.

In this illustrative embodiment, the named entity recognition componentmay also resolve structural ambiguity with regard to conjunctions (e.g.,“The Ways and Means Committee”, “Lewis and Clark”), possessives (e.g.,“Alice's Adventures in Wonderland”, “Britain's Tony Blair”), andprepositional attachment (e.g., “Whitney Museum of American Art”,“Whitney Museum in New York”) by using surface form informationextracted from the information resource, when available, with back-offto co-occurrence counts on the Web. The back-off method can be appliedrecursively, as follows: for each ambiguous term T₀ of the form T₁Particle T₂, where Particle is one of a possessive pronoun, acoordinative conjunction, or a preposition, optionally followed by adeterminer, and the terms T₁ and T₂ are sequences of capitalized wordsand particles, a web search can be performed on the search query ““T₁”“T₂””, which yields only search results in which the whole terms T₁ andT₂ appear. A collection of the top search results, for example the first200, may be evaluated to see how many also include the term T₀, as atest of whether T₀ is a reference to one single entity, or if T₁ and T₂are two separate entities conjoined in context.

In a third stage of pre-processing the text, shorter or abbreviatedsurface forms may be resolved to longer forms. It is not uncommon for anamed entity to be introduced in a document in a longer, formal versionof the name of the entity, and for at least some subsequent mentions ofthe entity to be made with abbreviated or more casual surface forms. Forexample, a text may introduce a reference to the named entity “FranklinDelano Roosevelt”, and then make several subsequent references to themore abbreviated or casual surface forms, “Franklin Roosevelt”,“President Roosevelt”, “Roosevelt”, or simply “FDR”, though somesubsequent references to the full name of the named entity may also bemade. A regular pattern consistent with this usage in the thresholdsearch results may be taken to indicate that a set of a longer namedentity with component forms of the named entity is indeed a regularrelationship between a named entity and surface forms of the namedentity in the text. Therefore, before attempting to solve semanticambiguity with subsequent steps of procedure 321, the system mayhypothesize in-document co-references and map short surface forms tolonger surface forms with the same dominant label. For example,“Roosevelt”/PERSON can be mapped to “Franklin Delano Roosevelt”/PERSON.

This is only one illustrative example of pre-processing named referencesand surface forms in a document. Additional pre-processing steps, suchas for resolving acronyms may also be resolved in a similar manner whenpossible. The system is not limited to any particular pre-processingsteps or to performing any pre-processing steps, in other embodiments.

Such pre-processing stages may be followed by extracting the contextualand category information from the information resource to disambiguatethe entities in the subject text, following the steps of procedure 321.Procedure 321 may produce the disambiguation output in any of a varietyof forms. For example, it may create hyperlinks in the subject text,from the named entities and surface forms of the named entities, toarticles in the information resource directed to the named entities. Or,in another embodiment, the system may provide a pop-up disambiguationoutput box adjacent to a pointer when the user hovers a pointer over asurface form, as depicted in FIG. 2. Other embodiments are not limitedto these illustrative examples, but may provide any form ofdisambiguation output.

In one illustrative embodiment, the disambiguation process may employ avector space model, in which a vectorial representation of the processeddocument is compared with vectorial representations of the named entityreferences stored in the named entity database: Once the surface formsin a subject text are identified and the in-document co-referenceshypothesized, the system may retrieve all possible entitydisambiguations of each surface form. Their entity indicators, such asthe labels and context indicators that occur in the document, may beaggregated into a document vector, which is subsequently compared withnamed entity vectors representing the named entity references of variouspossible entity disambiguations, so that one or more measures ofcorrelation between the vectors representing surface forms in the textand the vectors representing the entity indicators may be evaluated. Oneof the reference named entities may then be identified for a particularsurface form, that maximizes the similarity between the document vectorand the entity vectors. Or, in other embodiments, a reference namedentity is identified that in some other way is found to have a highcorrelation to the surface form in the text, relative to other candidatenamed entities.

The illustrative example of maximizing the similarity of the vectorsrepresenting the surface form from the subject text, and the identifiedreference named entity, may be elaborated on as follows, in accordancewith one illustrative embodiment. It may be well appreciated by thoseskilled in the art that a broad variety of other implementations may beanalogous to or approximate to the illustrative implementation describedhere, within the scope of various embodiments; and furthermore thatother embodiments may also be implemented with very substantialdifferences, that nevertheless accomplish the broad outlines of aspectsof the present disclosure.

In this illustrative example, a vector space model may be used toevaluate measures of correlation or similarity between elements of asubject text and entity indicators. In this illustrative embodiment,formally, let C={c₁, . . . ,c_(M)} be the set of known contextindicators from the information resource, and T={t₁, . . . ,t_(N)} bethe set of known labels. An entity e can then be represented as a vectorδ_(e)ε{0,1}^(M+N), with two components, δ_(e)|_(C)ε{0,1}^(M) andδ_(e)|_(T)ε{0,1}^(N), corresponding to the context information andcategory labels, respectively:

$\delta_{e}^{i} = \left\{ {{\begin{matrix}{1,} & {{if\_ c}_{i}{\_ is}{\_ a}{\_ context}{\_ indicator}{\_ for}{\_ entity}{\_ e}} \\{0,} & \text{otherwise}\end{matrix}\delta_{e}^{M + j}} = \left\{ \begin{matrix}{1,} & {{if\_ t}_{j}{\_ is}{\_ a}{\_ label}{\_ for}{\_ entity}{\_ e}} \\{0,} & \text{otherwise}\end{matrix} \right.} \right.$

Let ε(s) denote the set of entities that are known to have a surfaceform s. For example, in FIGS. 1 and 2, the named entities “ColumbiaUniversity” and “Space Shuttle Columbia” are two named entities thatboth share a common surface form, in “Columbia”. Let D be a document tobe analyzed and let S(D)={s₁, . . . ,s_(n)} be the set of surface formsidentified in D. A context vector may be built as d={d₁, . . .,d_(M)}εN^(M), where d_(i) is the number of occurrences of contextindicators c_(i) in D. To account for all possible disambiguations ofthe surface forms in D, an extended vector may also be built asdεN^(M+N) so that d|_(C)=d and

${\overset{\_}{d}\text{}_{T}} = {\sum\limits_{s \in {S{(D)}}}{\sum\limits_{e \in {ɛ{(s)}}}{\delta_{e}{\text{}_{T}.}}}}$

The goal in this illustrative embodiment is to find the assignment ofentities to surface forms s_(i)

e_(i),iε1 . . . n, that maximizes the agreement between δ_(δ)_(e′)|_(C)=d and d, as well as the agreement between the labels of anytwo entities δ_(e) _(i) |_(T) and δ_(e) _(j) |_(T). For example, thedocument may contain both the surface forms “Discovery” and “Columbia”.On one hand, the disambiguations “Space Shuttle Discovery” and “SpaceShuttle Columbia” would share a large number of category labels andthus, this assignment would result in a high agreement of their categorycomponents. On the other hand, the category components for thedisambiguations “Space Shuttle Discovery” an “Colombia (country)” wouldnot be likely to generate a significant measure of correlation/agreementbetween each other. This agreement maximization process is discussed inmore detail further below. In another illustrative example, agreementbetween different context indicators may be evaluated to maximize theagreement or correlation with entity indicators in the text. Onedocument that mentions “Columbia” may also include the text strings“NASA”, “Kennedy Space Center”, and “solid rocket booster”, leading toidentification of the surface form “Columbia” with the named entity“Space Shuttle Columbia”. Another document that mentions “Columbia” mayalso include the text strings “Bogota”, “Cartagena”, and “Àlvaro Uribe”,leading to identification of the surface form “Columbia” with the namedentity “Colombia (nation)”.

The agreement maximization process can be written as the followingEquation 1:

$\begin{matrix}{{{\underset{{({e_{1},\; \ldots \;,e_{n}})}{{\varepsilon ɛ}{(s_{1})}} \times \ldots \times {(s_{n})}}{\text{arg}\; \max}\sum\limits_{i = 1}^{n}} < {\delta_{e_{i}}\text{}_{C}}},{d > {+ {\sum\limits_{i = 1}^{n}\sum\limits_{\underset{j \neq 1}{j = 1}}^{n}}} < {\delta_{e_{i}}\text{}_{T}}},{{\delta_{e_{j}}\text{}_{T}} >},} & \left( {{Eq}.\mspace{14mu} 1} \right)\end{matrix}$

where <.,.> denotes the scalar product of vectors.

One potential issue with Equation 1 is that an erroneous assignment ofan entity to a surface form may interfere with the second term ofEquation 1. This issue may be addressed with another strategy to accountfor category agreement, which reduces the impact of erroneousassignments in a computationally efficient manner, includes attemptingto maximize agreement between the categories of the entitydisambiguation of each surface form and the possible disambiguations ofthe other surface forms in the subject document or text. In oneillustrative implementation, this may be equivalent to performing thefollowing Equation 2:

$\begin{matrix}{{{\underset{{({e_{1},\; \ldots \;,e_{n}})} \in {{ɛ{(s_{1})}} \times \ldots \times {(s_{n})}}}{\text{arg}\; \max}\sum\limits_{i = 1}^{n}} < \delta_{e_{i}}},{{\overset{\_}{d} - {\delta_{e_{i}}\text{}_{T}}} >}} & \left( {{Eq}.\mspace{14mu} 2} \right)\end{matrix}$

Using the definition of d and partitioning the context and categorycomponents, the sum in Equation 2 can be rewritten as

${\sum\limits_{i = 1}^{n}{< {\delta_{e_{i}}{_{C}{,{d > {+ \sum\limits_{i = 1}^{n}} < \delta_{e_{i}}}}}_{T}}}},{{\overset{\_}{d}{_{T}{- \delta_{e_{i}}}}_{T}}>={\sum\limits_{i = 1}^{n}{< {\delta_{e_{i}}{_{C}{,{d > {+ \sum\limits_{i = 1}^{n}} < \delta_{e_{i}}}}}_{T}}}}},{{\left( {\sum\limits_{j = 1}^{n}{\sum\limits_{e \in {ɛ{(s_{j})}}}\delta_{e}}} \right) - \delta_{e_{i}}}_{T}{>={\sum\limits_{i = 1}^{n}{< {\delta_{e_{i}}{_{C}{,{d > {+ {\sum\limits_{i = 1}^{n}\sum\limits_{\underset{j \neq 1}{j = 1}}^{n}}} < {\delta \; e_{i}}}}}_{T}}}}}},{{\sum\limits_{e \in {ɛ{(s_{j})}}}\delta_{e}} > \left( {q.e.d.} \right)}$

In this implementation, the maximization of the sum in Equation2 isequivalent to the maximization of each of its terms, which means thatthe computation reduces to

${\underset{e_{1} \in {ɛ{(s_{1})}}}{argmax} < \delta_{e_{i}}},{{\overset{\_}{d} - {\delta_{e_{i}}\text{}_{T}}} >},{i \in {1\mspace{11mu} \ldots \mspace{11mu} n}},$

or equivalently,

$\begin{matrix}{{\underset{e_{1} \in {ɛ{(s_{1})}}}{\text{arg}\; \max} < \delta_{e_{i}}},{\overset{\_}{d} > {- {{\delta_{e_{i}}_{T}}}^{2}}},{i \in {1\mspace{11mu} \ldots \mspace{11mu} n}}} & \left( {{Eq}.\mspace{14mu} 3} \right)\end{matrix}$

The disambiguation process following this illustrative embodimenttherefore may include two steps: first, it builds the extended documentvector, and second, it maximizes the scalar products in Equation 3. Invarious embodiments, it is not necessary to build the document vectorover all context indicators C, but only over the context indicators ofthe possible entity disambiguations of the surface forms in thedocument.

One illustrative embodiment may include normalizing the scalar productsby the norms of the vectors, and thereby computing the cosine distancesimilarity. In another illustrative embodiment, following Equation 3,the scalar products are not normalized by the norms of the vectors, butrather, an implicit accounting is made for the frequency with which asurface form is used to mention various entities and for the importanceof these entities, as indicated by entities that have longer articles inthe information resource, that are mentioned more frequently in otherarticles, and that tend to have more category tags and other labels,according to an illustrative embodiment. A broad variety of othermethods of evaluating the measures of similarity may be used indifferent embodiments, illustratively including Jensen-Shannondivergence, Kullback-Liebler divergence, mutual information, and avariety of other methods in other embodiments.

In some illustrative instances, one surface form can be used to mentiontwo or more different entities within the same text or document. Toaccount for such cases, the described disambiguation process may beperformed iteratively in this embodiment for the surface forms that havetwo or more disambiguations with high similarity scores with theextended document vector. This may be done by iteratively shrinking thecontext used for the disambiguation of each instance of such a surfaceform from document level to paragraph level, and if necessary, tosentence level, for example. For example, in FIG. 2, the surface form“Columbia” appears twice, fairly close together, but intended toindicate two different named entities. The disambiguation data may berestricted to the sentence level in the immediate proximity of these twosurface forms, or may concentrate the weightings assigned to entityindicators within the immediate sentence of the surface forms, indifferent embodiments. In one illustrative implementation, this wouldaccord an overwhelming weight to entity indicators such as “NASA” forthe first surface form of “Columbia”, while assigning overwhelmingweight to entity indicators such as “master's degree” for the secondsurface form of “Columbia”, thereby enabling them to be successfullydisambiguated into identifications with the named entities of the “SpaceShuttle Columbia” and “Columbia University”, respectively, according tothis illustrative embodiment.

In another illustrative implementation, a user may be able to indicate asubset of text to be evaluated for disambiguation of surface forms,where the subset may be selected from among a group of optional units oftext such as a document, a page, a paragraph, a sentence, or a manuallyselected portion of text.

In yet another illustrative example, a number of different candidatesurface forms that overlap each other may be identified in the sametext, and the different candidate surface forms may be separatelyevaluated to identify one of the overlapping surface forms that isassociated with one of the reference named entities in the surface formreference, for which the associated entity indicators have a relativelyhigh correlation to the text. A disambiguation output may then beprovided that indicates the identified surface form and the referencenamed entity associated with the identified surface form, in thisillustrative implementation.

Various embodiments of software and methods for automatic disambiguationmay be embodied as modules within applications, or as separateapplications that act on other text-associated applications, or may takeother forms relative to the document or other form of text on which theyoperate. An automatic disambiguation module or application may act upontext in any of a broad range of applications, which may illustrativelyinclude, but are not limited to: a word processing application, apresentation application, a spreadsheet application, a databaseapplication, an email application, an instant messaging application, aninformation manager application, a web page application, a web pageediting application, a reference work application, a fixed-layoutdocument application, a desktop publishing application, a diagrammingapplication, a project management application, a form developerapplication, a customer relationship management application, anenterprise resource planning application, a field services application,a retail management application, a social networking application, a taxpreparation application, a finance management application, an accountingapplication, and a game application, for example.

FIG. 4 illustrates an example of a suitable computing system environment400 on which various embodiments may be implemented. For example,various embodiments may be implemented as software applications,modules, or other forms of instructions that are executable by computingsystem environment 400 and that configure computing system environment400 to perform various tasks or methods involved in differentembodiments. A software application or module associated with anillustrative implementation of a speech recognition system using hiddentrajectory modeling with differential cepstra may be developed in any ofa variety of programming or scripting languages or environments. Forexample, it may be written in C#, F#, C++, C, Pascal, Visual Basic,Java, JavaScript, Delphi, Eiffel, Nemerle, Perl, PHP, Python, Ruby,Visual FoxPro, Lua, or any other programming language. It is alsoenvisioned that new programming languages and other forms of creatingexecutable instructions will continue to be developed, in which furtherembodiments may readily be developed.

Computing system environment 400 as depicted in FIG. 4 is only oneexample of a suitable computing environment for implementing variousembodiments, and is not intended to suggest any limitation as to thescope of use or functionality of the claimed subject matter. Neithershould the computing environment 400 be interpreted as having anydependency or requirement relating to any one or combination ofcomponents illustrated in the exemplary operating environment 400.

Embodiments are operational with numerous other general purpose orspecial purpose computing system environments or configurations.Examples of well-known computing systems, environments, and/orconfigurations that may be suitable for use with various embodimentsinclude, but are not limited to, personal computers, server computers,hand-held or laptop devices, multiprocessor systems,microprocessor-based systems, set top boxes, programmable consumerelectronics, network PCs, minicomputers, mainframe computers, telephonysystems, distributed computing environments that include any of theabove systems or devices, and the like.

Embodiments may be described in the general context ofcomputer-executable instructions, such as program modules, beingexecuted by a computer. Generally, program modules include routines,programs, objects, components, data structures, etc. that performparticular tasks or implement particular abstract data types. Someembodiments are designed to be practiced in distributed computingenvironments where tasks are performed by remote processing devices thatare linked through a communications network. In a distributed computingenvironment, program modules are located in both local and remotecomputer storage media including memory storage devices. As describedherein, such executable instructions may be stored on a medium such thatthey are capable of being read and executed by one or more components ofa computing system, thereby configuring the computing system with newcapabilities.

With reference to FIG. 4, an exemplary system for implementing someembodiments includes a general-purpose computing device in the form of acomputer 410. Components of computer 410 may include, but are notlimited to, a processing unit 420, a system memory 430, and a system bus421 that couples various system components including the system memoryto the processing unit 420. The system bus 421 may be any of severaltypes of bus structures including a memory bus or memory controller, aperipheral bus, and a local bus using any of a variety of busarchitectures. By way of example, and not limitation, such architecturesinclude Industry Standard Architecture (ISA) bus, Micro ChannelArchitecture (MCA) bus, Enhanced ISA (EISA) bus, Video ElectronicsStandards Association (VESA) local bus, and Peripheral ComponentInterconnect (PCI) bus also known as Mezzanine bus.

Computer 410 typically includes a variety of computer readable media.Computer readable media can be any available media that can be accessedby computer 410 and includes both volatile and nonvolatile media,removable and non-removable media. By way of example, and notlimitation, computer readable media may comprise computer storage mediaand communication media. Computer storage media includes both volatileand nonvolatile, removable and non-removable media implemented in anymethod or technology for storage of information such as computerreadable instructions, data structures, program modules or other data.Computer storage media includes, but is not limited to, RAM, ROM,EEPROM, flash memory or other memory technology, CD-ROM, digitalversatile disks (DVD) or other optical disk storage, magnetic cassettes,magnetic tape, magnetic disk storage or other magnetic storage devices,or any other medium which can be used to store the desired informationand which can be accessed by computer 410. Communication media typicallyembodies computer readable instructions, data structures, programmodules or other data in a modulated data signal such as a carrier waveor other transport mechanism and includes any information deliverymedia. The term “modulated data signal” means a signal that has one ormore of its characteristics set or changed in such a manner as to encodeinformation in the signal. By way of example, and not limitation,communication media includes wired media such as a wired network ordirect-wired connection, and wireless media such as acoustic, RF,infrared and other wireless media. Combinations of any of the aboveshould also be included within the scope of computer readable media.

The system memory 430 includes computer storage media in the form ofvolatile and/or nonvolatile memory such as read only memory (ROM) 431and random access memory (RAM) 432. A basic input/output system 433(BIOS), containing the basic routines that help to transfer informationbetween elements within computer 410, such as during start-up, istypically stored in ROM 431. RAM 432 typically contains data and/orprogram modules that are immediately accessible to and/or presentlybeing operated on by processing unit 420. By way of example, and notlimitation, FIG. 4 illustrates operating system 434, applicationprograms 435, other program modules 436, and program data 437.

The computer 410 may also include other removable/non-removablevolatile/nonvolatile computer storage media. By way of example and notlimitation, FIG. 4 illustrates a hard disk drive 441 that reads from orwrites to non-removable, nonvolatile magnetic media, a magnetic diskdrive 451 that reads from or writes to a removable, nonvolatile magneticdisk 452, and an optical disk drive 455 that reads from or writes to aremovable, nonvolatile optical disk 456 such as a CD ROM or otheroptical media. Other removable/non-removable, volatile/nonvolatilecomputer storage media that can be used in the exemplary operatingenvironment include, but are not limited to, magnetic tape cassettes,flash memory cards, digital versatile disks, digital video tape, solidstate RAM, solid state ROM, and the like. The hard disk drive 441 istypically connected to the system bus 421 through a non-removable memoryinterface such as interface 440, and magnetic disk drive 451 and opticaldisk drive 455 are typically connected to the system bus 421 by aremovable memory interface, such as interface 450.

The drives and their associated computer storage media discussed aboveand illustrated in FIG. 4, provide storage of computer readableinstructions, data structures, program modules and other data for thecomputer 410. In FIG. 4, for example, hard disk drive 441 is illustratedas storing operating system 444, application programs 445, other programmodules 446, and program data 447. Note that these components can eitherbe the same as or different from operating system 434, applicationprograms 435, other program modules 436, and program data 437. Operatingsystem 444, application programs 445, other program modules 446, andprogram data 447 are given different numbers here to illustrate that, ata minimum, they are different copies.

A user may enter commands and information into the computer 410 throughinput devices such as a keyboard 462, a microphone 463, and a pointingdevice 461, such as a mouse, trackball or touch pad. Other input devices(not shown) may include a joystick, game pad, satellite dish, scanner,or the like. These and other input devices are often connected to theprocessing unit 420 through a user input interface 460 that is coupledto the system bus, but may be connected by other interface and busstructures, such as a parallel port, game port or a universal serial bus(USB). A monitor 491 or other type of display device is also connectedto the system bus 421 via an interface, such as a video interface 490.In addition to the monitor, computers may also include other peripheraloutput devices such as speakers 497 and printer 496, which may beconnected through an output peripheral interface 495.

The computer 410 may be operated in a networked environment usinglogical connections to one or more remote computers, such as a remotecomputer 480. The remote computer 480 may be a personal computer, ahand-held device, a server, a router, a network PC, a peer device orother common network node, and typically includes many or all of theelements described above relative to the computer 410. The logicalconnections depicted in FIG. 4 include a local area network (LAN) 471and a wide area network (WAN) 473, but may also include other networks.Such networking environments are commonplace in offices, enterprise-widecomputer networks, intranets and the Internet.

When used in a LAN networking environment, the computer 410 is connectedto the LAN 471 through a network interface or adapter 470. When used ina WAN networking environment, the computer 410 may include a modem 472or other means for establishing communications over the WAN 473, such asthe Internet. The modem 472, which may be internal or external, may beconnected to the system bus 421 via the user input interface 460, orother appropriate mechanism. In a networked environment, program modulesdepicted relative to the computer 410, or portions thereof, may bestored in the remote memory storage device. By way of example, and notlimitation, FIG. 4 illustrates remote application programs 485 asresiding on remote computer 480. It will be appreciated that the networkconnections shown are exemplary and other means of establishing acommunications link between the computers may be used.

FIG. 5 depicts a block diagram of a general mobile computingenvironment, comprising a mobile computing device and a medium, readableby the mobile computing device and comprising executable instructionsthat are executable by the mobile computing device, according to anotherillustrative embodiment. FIG. 5 depicts a block diagram of a mobilecomputing system 500 including mobile device 501, according to anillustrative embodiment. Mobile device 501 includes a microprocessor502, memory 504, input/output (I/O) components 506, and a communicationinterface 508 for communicating with remote computers or other mobiledevices. In one embodiment, the afore-mentioned components may becoupled for communication with one another over a suitable bus 510.

Memory 504 is implemented as non-volatile electronic memory such asrandom access memory (RAM) with a battery back-up module (not shown)such that information stored in memory 504 is not lost when the generalpower to mobile device 500 is shut down. A portion of memory 504 isillustratively allocated as addressable memory for program execution,while another portion of memory 504 is illustratively used for storage,such as to simulate storage on a disk drive.

Memory 504 includes an operating system 512, application programs 514 aswell as an object store 516. During operation, operating system 512 isillustratively executed by processor 502 from memory 504. Operatingsystem 512, in one illustrative embodiment, is a WINDOWS® CE brandoperating system commercially available from Microsoft Corporation.Operating system 512 is illustratively designed for mobile devices, andimplements database features that can be utilized by applications 514through a set of exposed application programming interfaces and methods.The objects in object store 516 are maintained by applications 514 andoperating system 512, at least partially in response to calls to theexposed application programming interfaces and methods.

Communication interface 508 represents numerous devices and technologiesthat allow mobile device 500 to send and receive information. Thedevices include wired and wireless modems, satellite receivers andbroadcast tuners to name a few. Mobile device 500 can also be directlyconnected to a computer to exchange data therewith. In such cases,communication interface 508 can be an infrared transceiver or a serialor parallel communication connection, all of which are capable oftransmitting streaming information.

Input/output components 506 include a variety of input devices such as atouch-sensitive screen, buttons, rollers, and a microphone as well as avariety of output devices including an audio generator, a vibratingdevice, and a display. The devices listed above are by way of exampleand need not all be present on mobile device 500. In addition, otherinput/output devices may be attached to or found with mobile device 500.

Mobile computing system 500 also includes network 520. Mobile computingdevice 501 is illustratively in wireless communication with network520—which may be the Internet, a wide area network, or a local areanetwork, for example—by sending and receiving electromagnetic signals599 of a suitable protocol between communication interface 508 andwireless interface 522. Wireless interface 522 may be a wireless hub orcellular antenna, for example, or any other signal interface. Wirelessinterface 522 in turn provides access via network 520 to a wide array ofadditional computing resources, illustratively represented by computingresources 524 and 526. Naturally, any number of computing devices in anylocations may be in communicative connection with network 520. Computingdevice 501 is enabled to make use of executable instructions stored onthe media of memory component 504, such as executable instructions thatenable computing device 501 to implement various functions of automaticdisambiguation based on a reference resource, in an illustrativeembodiment.

Although the subject matter has been described in language specific tostructural features and/or methodological acts, it is to be understoodthat the subject matter defined in the appended claims is notnecessarily limited to the specific features or acts described above.Rather, the specific features and acts described above are disclosed asexample forms of implementing the claims. As a particular example, whilethe terms “computer”, “computing device”, or “computing system” mayherein sometimes be used alone for convenience, it is well understoodthat each of these could refer to any computing device, computingsystem, computing environment, mobile device, or other informationprocessing component or context, and is not limited to any individualinterpretation. As another example, various embodiments may be appliedto automatic disambiguation of documents or other files in English,Spanish, Chinese, or any other human language. As another particularexample, while many embodiments are presented with illustrative elementsthat are widely familiar at the time of filing the patent application,it is envisioned that many new innovations in computing technology willaffect elements of different embodiments, in such aspects as userinterfaces, user input methods, computing environments, and computingmethods, and that the elements defined by the claims may be embodiedaccording to these and other innovative advances while still remainingconsistent with and encompassed by the elements defined by the claimsherein.

1. A method comprising: identifying a surface form of a named entity ina text, wherein the surface form is associated in a surface formreference with one or more reference named entities, and each of thereference named entities is associated in a named entity reference withone or more entity indicators; evaluating one or more measures ofcorrelation among one or more of the entity indicators, and the text;identifying one of the reference named entities for which the associatedentity indicators have a relatively high correlation to the text; andproviding a disambiguation output that indicates the identifiedreference named entity to be associated with the surface form of thenamed entity in the text.
 2. The method of claim 1, wherein the entityindicators comprise one or more labels applied to a respective namedentity in an information resource.
 3. The method of claim 2, wherein theone or more labels comprise at least one element selected from among: atag; a category; a heading; a title; a section name; and a list name. 4.The method of claim 1, wherein the entity indicators comprise one ormore context indicators applied to a respective named entity in aninformation resource.
 5. The method of claim 4, wherein the contextindicators comprise at least one element selected from among: anattribute included in a title of a document about the respective namedentity in the information resource; an attribute appearing proximate tothe respective named entity in the information resource; an attributethat links to a document about the respective named entity in theinformation resource; and an attribute that is linked from a documentabout the respective named entity in the information resource.
 6. Themethod of claim 1, further comprising: extracting a set of surface formsand entity indicators associated with a plurality of named entities fromone or more information resources; and storing the surface forms andnamed entities in a surface form reference, comprising a data collectionindexed by the surface forms and indicating the named entitiesassociated with each of the surface forms; and storing the namedentities and entity indicators in a named entity reference, comprising adata collection indexed by the named entities and containing the entityindicators associated with each of the named entities; wherein thesurface form of a named entity in a text is identified from among thesurface forms stored in the surface form reference, and the one or moremeasures of correlation are evaluated between the text and the extractedentity indicators stored in the named entity reference.
 7. The method ofclaim 6, wherein the one or more information resources are selected fromamong a group consisting of: a website; a related group of websites; aweb publication; an encyclopedia; a directory; an atlas; and a citationindex.
 8. The method of claim 6, wherein the surface forms of arespective named entity are extracted from at least one element fromamong a group consisting of: a title of a document about the respectivenamed entity; a title of a document that redirects to the document aboutthe respective named entity; a title of a document that disambiguates asurface form to the respective named entity as one possibledisambiguation; and the text of a link to a document about therespective named entity.
 9. The method of claim 6, wherein the extractedentity indicators comprise context indicators extracted from at leastone of the information resources, wherein the context indicatorscomprise elements of text associated with the respective named entities,in at least one of the information resources.
 10. The method of claim 6,wherein the extracted entity indicators comprise labels extracted fromat least one of the information resources, wherein the labels compriseclassifying identifiers applied to the respective named entities in atleast one of the information resources.
 11. The method of claim 1,further comprising: identifying a plurality of surface forms thatoverlap within the text; identifying one of the overlapping surfaceforms that is associated with one of the reference named entities in thesurface form reference, for which the associated entity indicators havea relatively high correlation to the text; and providing adisambiguation output that indicates the identified surface form and thereference named entity associated with the identified surface form. 12.The method of claim 1, further comprising receiving a user inputindicating the text comprising the surface form for which acorresponding reference named entity is to be identified.
 13. The methodof claim 1, further comprising receiving an indication, from atext-associated application, of a block of text associated with theapplication, and providing one or more disambiguation outputs thatindicate identified reference named entities to be associated with oneor more surface forms within the block of text.
 14. The method of claim13, wherein the text-associated application comprises at least oneapplication selected from among a group of options consisting of: a wordprocessing application, a presentation application, a spreadsheetapplication, a database application, an email application, an instantmessaging application, an information manager application, a web pageapplication, a web page editing application, a reference workapplication, a fixed-layout document application, a desktop publishingapplication, a diagramming application, a project managementapplication, a form developer application, a customer relationshipmanagement application, an enterprise resource planning application, afield services application, a retail management application, a socialnetworking application, a tax preparation application, a financemanagement application, an accounting application, and a gameapplication.
 15. The method of claim 1, wherein evaluating the one ormore measures of similarity comprises applying different weights to atleast one of: different types of the entity indicators; proximity of theentity indicators to the surface form of the named entity within thetext; number of common labels; or number of links among each other ofentity indicators extracted from documents that link to or are linkedfrom a document about an associated reference named entity.
 16. Themethod of claim 1, wherein evaluating the one or more measures ofsimilarity comprises using at least one element from a group consistingof: a vector space model; cosine similarity; Jensen-Shannon divergence;Kullback-Liebler divergence; and mutual information.
 17. The method ofclaim 1, wherein the text to be evaluated for disambiguation of surfaceforms may be selected from among a group of optional units of textconsisting of: a document, a page, a paragraph, a sentence, and amanually selected portion of text.
 18. The method of claim 17, furthercomprising first evaluating the one or more measures of similaritybetween a larger one of the units of text and the one or more entityindicators, and if more than one of the reference named entities isidentified as having associated entity indicators with a relatively highcorrelation to the entity indicators in the text, then evaluating theone or more measures of correlation between an iteratively smaller oneof the units of text and the one or more entity indicators, until aunique reference named entity is identified as having associated entityindicators with a relatively high correlation to the entity indicatorsin the text.
 19. A computer-readable medium comprisingcomputer-executable instructions which, when executed by a computingdevice, enable the computing device to prepare and apply an automaticdisambiguation system, comprising steps of: extracting a collection ofsurface forms associated with named entities from an informationresource; extracting a collection of labels associated with the namedentities from the information resource; extracting a collection ofcontext indicators associated with the named entities from theinformation resource; when provided with a surface form in a textsample, evaluating a measure of correlation of entity indicatorsassociated with the surface form in the text sample with the labels andthe context indicators associated with the named entities associatedwith the surface form in the collection of surface forms; and providingan output, based on the measure of correlation, indicating one of thenamed entities to be a disambiguation of the surface form in the textsample.
 20. A computer-readable medium comprising one or more databases,the one or more databases comprising a collection of reference surfaceforms and a collection of named entities, wherein each of the referencesurface forms is associated with one or more of the named entities, andeach of the named entities is associated with one or more entityindicators extracted from one or more reference works in which the oneor more entity indicators are associated with the named entities;wherein the computer-readable medium further comprisescomputer-executable instructions that, when executed by a computingdevice, configure the computing device to disambiguate one or morepolysemic words in a sample of text, comprising steps of: identifying arespective polysemic word with one of the reference surface forms;evaluating a similarity measure between the entity indicators associatedwith the named entities associated with the reference surface forms, andentity indicators associated with the respective polysemic word in thesample of text; identifying one of the named entities as having arelatively high similarity measure between its associated entityindicators and the entity indicators associated with the respectivepolysemic word; and providing a disambiguation output indicating thepolysemic word to be associated with the identified named entity.